Land cession refers to the formal transfer of land from one entity to another, often through treaties or agreements. In the context of U.S.-Mexico relations, land cession was a critical outcome of the Treaty of Guadalupe Hidalgo in 1848, which ended the Mexican-American War and resulted in Mexico ceding a significant portion of its territory to the United States. This event reshaped the geopolitical landscape of North America and had lasting implications for both nations and their respective populations.